1. Field of the Invention
This invention relates to a head-up display apparatus installed at a vehicle, especially to the head-up display including a mirror holder to be turned up/down.
2. Description of the Related Art
The patent reference 1 shows such kind of a usual head-up display apparatus. The usual head-up display apparatus will be described with reference to FIGS. 5, 6. FIG. 5A shows a condition that the usual head-up display apparatus is turned down forwardly. FIG. 5B shows a condition that the usual head-up display apparatus is turned up. FIG. 6 is a plan view of the head-up display apparatus to be turned down forwardly shown in FIG. 5.
The usual head-up display apparatus includes a display unit 92 received in a box-shape housing 91 for outputting a predetermined display light, a mirror 93, a front side cover 94 forming a front side wall of the housing 91 and acting open/close around an axis at one part of the housing 91, a mirror 96 to be turned up/down around an axis at the other part of the housing 91 as shown in FIGS. 5A, 5B. The front side cover 94 has a rotation shaft 941 and a rotation guide pin 942. The mirror 96 is provided with a hinge 97 for making the mirror 96 capable to act open/close. The hinge 97 has a rotation shaft 971 and a rotation guide pin 972. The front side cover 94 and the mirror 96 act open/close interlockingly around the rotation shaft 941 and the rotation shaft 971 by forces supplied on the pin 942 and pin 972.
According to such structure, in a condition that the mirror 96 is turned down forwardly, the front side cover 94 is closed as shown in FIG. 5A. On the other hand, in a condition that the mirror 96 is turned up, the front side cover 94 is opened interlockingly with the mirror 96 as shown in FIG. 5B.
In FIG. 5B, the mirror 96 changes light path of a display light L outputted from the display unit 92 and reflected by a mirror 93, and provides final display information to an eye point E predetermined for a driver sitting on a driver seat. Usually, there is a plurality of eye points in a range between an upper limit and a lower limit. Therefore, the eye point can be called an eye range.
The patent reference 1 related with the present invention is: Japan Patent Application Laid Open No. H9-315182.